"A Separation" charts the despair of two families

Everything in A Separation hangs on one moment. It's very quick. An enraged man and woman are fighting. She is struggling to get into his apartment, and he is struggling to get her out. Then she is gone, the door is closed, and the moment is over.

Later, the man and woman tell different stories about what happened, and their disagreement plays out in court. It might be just the stuff of some primetime legal drama, except that Iranian writer-director Asghar Farhadi's deeply compelling film unfolds in complex, unsettling ways.

The complexity has partly to do with big themes Farhadi invokes: gender relations, aging parents, politics, class, religion, honor, shame. But the real triumph of A Separation, which is nominated for a Foreign Language Film Oscar this year, is that Farhadi's observations about families are so keen. The incident at the apartment door throws together two unhappy families, and you've never seen so many secrets and lies in a domestic drama.

A Separation begins with a separation. Simin (Leila Hatami) wants a divorce. She would like to leave Iran and take her adolescent daughter Termeh (Sarina Farhadi) with her. But her husband, Nader (Peyman Moadi), will not go, because he must take care of his father (Ali-Asghar Shahbazi), who has Alzheimer's. "These are not good reasons for a divorce," the judge tells Simin. Case dismissed.

So Simin moves out of the family's comfortably middle-class apartment. Nader needs help with his father, so he hires a working-class caregiver, Razieh (Sareh Bayat). But it's not a good fit. She has to telephone for emergency religious dispensation just to change the old man's soiled pants. Her volatile husband, Hodjat (Shahab Hosseini), takes the job, but then he is imprisoned for debts. So Razieh goes back, young daughter Somayeh (Kimia Hosseini) in tow.

Then, in a searing scene, Nader fires Razieh after he comes home to find her gone. His father is on the floor in a state of collapse, and some money is missing. She returns, and the confrontation at the door follows. She falls down the stairs - or did he push her? Later comes terrible news. She was pregnant, and she lost her baby in the fall - or did she? A confrontation unfolds before a weary, overworked judge (Babak Karimi), who because of Razieh's miscarriage charges Nader with murder.

The truth is all but impossible to sort out. The characters evade and lie, as people will, or they make mistakes, each for different reasons. Hodjat is a hothead whose poverty makes him anxious and resentful. Because of Razieh's religion, she's not always truthful about where she goes and whom she sees.

Meanwhile, Nader tries to keep his family together, and avoid jail, by eliding certain inconvenient facts. He's the most fascinating and troubling character. He adores his daughter Termeh and is protective of her, but in a key scene, he passive-aggressively puts her in an impossible situation no teenager is equipped to handle. Later, a judge who's questioning her puts her in an equally impossible situation.

My heart goes out to Termeh, and to little Somayeh. Late in the film, the two girls share a knowing look that makes me despair. They're only observers in their families' dispute, but in a way, they're at the center of this sprawling, intense film, one that's dense with ideas and rich with indelible characters.